Syringe



May l, 1951 c. B. BuRNslDE SYRINGE Filed Nov. 24, 194'? Patented May 1, 1951 lUN lT-ED STATE-S PAT ENT OFFICE SYRINGE Carl- B. Burnside, Indianapolis,` Ind.,fassignor to A Eli Lilly and` Company,4 Indianapolis, .Ind., a corporationoflndiana -Application-November 24, 1947, Serial No; 787,745

3 Claims. y1 ...Myzinvention relates to medicinalxhypodermc syringes 1 and v.more particularly .to hypodermic syringes of a: disposabletype in which the syringe .may serveV as a container of a` medicament.

AHIn the past, Vmanyxsyringes'of a'disposable type v rhavebeen proposed formedicinal uses. These :syrin'gesfwhile satisfactory in some respects, possessseveralv disadvantages. They are, vingeneraL- expensive:tofmanufacture. `They usually require a plurality of' elements-whose production is :v diiiicult andwhosev assemblyl contributes ma- Adermic needle attached to the syringe is positioned in a.-blood vesseL-aposition which may-o1' -mayv not 'bedesirable, depending on the purpose for which the syringe isbeingused.

object Aof vmy inventionfis .to .provide k.a medicinal syringe.v of. low costof. manufacture so thatl it is-.economically feasible.. to discard the syringe .after asingleuse. .-Another. object. is to vprovide-a syringe composed of a minimum number of parts so that it may beassembledcheaply. Another, objectgis to, provide a syringe whose several parts may perform more than-one function thereby decreasing the total number ofl parts .necessary for effective operation. Another object is to provide a syringe Whichis easily sterilized, and which when l.assembled will remain 'sterile and ready for immediate use. Another object is to provide a syringe capable of serving as a containerof a medicament ofthe like, and capable of maintaining its contents in sterile condition, Otherob'jects will become apparent as the following disclosureand description proceed.

*In fullling the above and other objects, I have provided a syringev composed of but three separable parts; avbarrel having at one end a hypodermic needle Whose lumen communicates `with theintericrof the barrel, a piston contained and operative Within said barrel, f and va needle 'sheath securable ina-protective position to the vneedle-bearing'end of said barrel. 'The needle sheathv and-the piston bear co-operative attachment means whereby they may be securely joined to form a unitaryplunger which may-be advanced crfretracted Within the' barrel' thus permittingl expulsionfof. a y'liquidf contained yin the barrel, or

. aspiration.

(Cl. 12S-218) Int/che. appendedidrawings in Whichslikenumvbers refer to like parts, Fig. I .is aview in longitudinal. section of one embodiment of' myi invention. Fig; II is a view'similar to' Fig. I but` showing the"contamination-preventing needle 'sheath attachedto. the piston. Fig. IIIv is an elevation. of the needlef'end of the. construction Ashovvn in Fig. II. Fig. IV is a'sectionalfview ofy a disassembled piston andneedle sheath showing a bayonet type attachment means. iFig; V is aifragmentarysectional view showing afmetalscrevv moldedfinira needle sheath. .fFig VI isia fragmentary'view of a syringe.' havingian elongatedlshank vviththe hypodermic:y needle i. extendingVV partially through 'the shank. :FigHVII is a .sectional` view.V oft-an alternative: form'iof needleV sheath' and a Ifragmentaryvievv'of abarrel=.and"shank adapted to receive theneedle sheath. Fig. VIII is a sectional View of an alternative mode of securing the needle sheath in protective position over. the hypodermic needle.

.In 'one' embodiment of myinventionA as shown in Figs.. I, VIIfand III, barrel 4 lis a'hollow cylinder formed ofanysuitable material such as .a moldable plastic, preferablyra" transparentk plastic. 1A medicament,: or .like liquid; 24; is'. containedV Within. barrel'` 4. i 'Flangef I 0, Lconveniently molded' integrally with barrel 4,'serves as a nge'rhold-'when the syringe is used. One end of barrel 4 terminates inishankl -moldedV about the hypodermic needle 8, 4which isi so"positi'oned.that` the lumen of itlie; needle communicates with the interior of barrel' 4. V'Secure bonding of the needle to the barrel' and shankmay beobtainedfby employingva needle'havingzaI roughenedv surfaceor, as illustrated, Abybending the needle slightly "to create offset portions. `Piston I2 vvhichts snugly in thebarrel is madeofan elastic material, forexample, rubber, and contains a molded insert I 1i. which is constructed cfa rigid-material, for example, metal, hard rubber or plastic, and which is provided with adrilledA and threaded hole I6. Needle sheath I8 which may be made ofthe same materialas the barrel, is equipped at -one end `vvitha screwl 22l adapted to engage threadedvhole I6 inlinsert I 4 of piston I2. Screw 22 may be of -plastic and .molded with needle sheath' I8, or may be of metalI or otherlsuitable material-V and' imbedded. inthe `needle sheathffas shovvnlin Fig. lJV. Sheath I8 desirably-isoffan external' diameter slightly smaller than' the-1internalf-diameter -of thelbarrel so that uponi removal'. of thefsheathfrom itsrpositicnover-the needleand insertion of` the'threaded portion? 22 into. hole Y I6, the combination of "Stopper and sheath forms a unitary plunger which may readily slide within the barrel but yet will allow relatively little lateral motion. Preferably, the piston is positioned a short distance within the barrel, so that for aspiration purposes the piston may be retracted for a distance Without having it come clear of the barrel. The internal diameter of the needle sheath is such that it will engage shank 6, which is slightly tapered to receive the sheath. Thus, forcing the sheath over the shank gives a secure frictional attachment. Within the needle sheath is plug 20 which is made of a punctureable material, for example, rubber or cork. Thus when the sheath is in protective position over needle 8 as shown in Fig. I, and is frictionally engaging shank 6, the hypodermic needle is imbedded in the plug thus occluding the needle and preventing leakage of the contents of barrel 4. Desirably, the plug is cemented or otherwise secured in position within the needle sheath since by such construction the plug is removed simultaneously with the sheath and there is avoided the necessity of risking contamination by touching with the fingers anything intimately in contact with the needle.

In assembling and lling my disposable syringe, the barrel, sheath, and stopper assemblies are sterilized by any of numerous suitable methods and sheath i8 is then placed over needle 8 and is forced on shank 8 until secure attachment is obtained. Barrel 4 is then filled to the desired extent with medicament or other liquid 24 and piston I2 is inserted, these operations being carried out under sterile conditions. Once assembled, the needle and the syringe contents will remain sterile and suitable for injection purposes. The assembly may then be placed in a suitable box or other wrapping and distributed to the trade ready for immediate use.

When it is desired to use the syringe for injection, the sheath is removed from the needle and is attached to the piston as described above. The syringe may then be used as a common Luer syringe, its construction permitting aspiration to determine whether the needle is located within or without a blood vessel, and permitting a ready injection of the medicament contained therein. After the syringe has been used, it may be discarded.

It will be obvious that numerous attachment means may be employed for attaching the needle sheath to the piston. As shown in Fig. V, a metal screw tip may be molded integrally with the sheath. As shown in Fig. IV, insert I4 and sheath I8 may be constructed so as to form a bayonet type of attachment device. When this attachment means is employed, a needle sheath of the form illustrated in Fig. VII may be used. This form of sheath may be held in needle-protective position by providing shank 6 with pins 30 to enga-ge bayonet slots 28 in the sheath, and may be attached to the piston as shown in Fig. IV. Other' similar attachment means for securing the needle sheath to the piston will be apparent. Likewise, alternatives may be employed for securing the needle sheath in needle-protective position. Illustratively, as shown in Fig. VIII, sheath I8 is constructed with an enlarged end portion which frictionally engages barrel 4.

A modification of my syringe which aords a convenient method of observing the results of aspiration is shown in Fig. VI. In this construction shank 6 is somewhat elongated and needle 8 is molded in the shank in such a position that it does n ot extend entirely through the shank, but

communicatesI with the interior of barrel 4 through conduit 28. Thus when blood is encountered in the aspiration, it is immediately visible in conduit 28. This construction is particularly advantageous when the medicaments being injected are so opaque that it is difficult with a syringe of usual construction to determine whether any blood is being drawn into the syringe barrel.

Because of its unique construction, my syringe may be used for the collection of sterile liquid samples as well as the dispensing of medicaments. For example, it may be used for collecting blood samples. For such use, the syringe parts are sterilized, and under sterile conditions are assembled in the form illustrated in Fig. I, with the barrel empty. The syringe is then ready for boxing and transmission to a user. For collection of a blood sample, the needle sheath is removed from the needle and fastened to the piston, and the plunger consisting of the needle sheath and stopper is advanced to expel the air from the barrel. The needle is then inserted in the blood vessel and the sample of blood is drawn into the syringe by retraction of the plunger. The needle sheath is then transferred from plunger position to needle-protective position, thus occluding the needle and protecting the sample from contamination. The filled syringe forms a sealed package which may be wrapped or boxed in any convenient manner and transmitted to a laboratory for such tests on the blood sample as may be desirable or necessary.

I claim:

1. In a disposable syringe, in combination, a medicament containing barrel terminating at one end in a reduced, transparent, elongate, projecting shank communicating with said barrel and having a hypodermic needle integrally, permanently and immovably affixed within a portion of said shank and so positioned that the lumen of said needle communicates with the interior of said shank, a slidable piston in said barrel, a needleprotecting sheath adapted to enclose said needle and frictionally to engage said shank, and attachment means for joining said piston and one end of said needle sheath, said means comprising a screw-receiving portion of said piston and a screw threaded projection on one end of said needle sheath whereby said piston and said needle sheath may be joined to form a plunger which by manipulation of the needle sheath portion may be advanced and retracted within said barrel, said transparent, elongate shank serving to facilitate observation of results of aspiration as said piston is retracted within said barrel.

2. In a container for liquid medicaments and the like, a barrel containing medicament having at one end a hypodermic needle directly communicating and integral therewith, a slidable piston in said barrel spaced from the needle end of said barrel, a needle sheath enveloping said needle, one end of said sheath attachable at the needle end of said barrel and the other end of the sheath having therein a puncturable plug occluding the needle when said sheath is in needle-protective position, and co-operative attachment means on said sheath and said piston whereby said sheath and said piston may be assembled so that upon removal of said sheath from needle-protective position and assembly with said piston said hypodermic needle is freed from occlusion and said piston and sheath form a unitary plunger which may be advanced and 5 retracted Within said barrel thereby converting said container into a syringe.

3. In a disposable syringe, in combination, a barrel having a hypodermic needle integral therewith at one end with the lumen of the needle communicating directly with the interior of said barrel at said one end, a fluid-medicament sealing piston slidably mounted in said barrel adjacent to the opposite end thereof, a needle sheath having means` at one end for detachably mounting the sheath upon said one end of said barrel and adapted when so mounted to spacedly encase the projecting needle including its free end, stopper means xedly contained in the opposite end of said sheath and engageable with said free end of said needle to prevent discharge of medicament therefrom when said sheath is mounted in needle protective position, and cooperative attaching means associated with said needle sheath and with said piston whereby the latter may be joined to the former for advancing or retracting said 6 piston in said barrel, said lumen being unstoppered incident to such joining of the sheath and piston.

CARL B. BURNSIDE. 

